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Encyclopedia of Marine and Energy Technology

Damage Survivability Information (DSI)


An analysis of different damage scenarios for standard loading conditions. In the event of damage to a ship, an assessment of the exact impact of the damage on the vessel’s stability is quite difficult. To be able to make correct decisions, while under the extreme stress of an emergency situation, masters shall have an understanding of the survival characteristics of their ships.

Unfortunately the statutory damage stability calculations have very limited value to understand real behavior of the vessel with a particular compartment or group of compartments flooded. In many cases damage scenarios analysed in order to attain a required subdivision index are pure theoretical, far away from real damages. In addition stability characteristics after damage are calculated for worst (minimum) values of GM only assuming empty tanks.

For these reasons it is necessary to analyse different damage scenarios for typical loading cases from the Loading and Stability Manual in order to understand ship’s behaviour after flooding and provide masters with a rapid first indication of the implications that damage will have on the ship’s stability performance, allowing them to plan their damage control in advance.

Fractures of side shell plating, fractures of side structures, groundings and bow crushings should be investigated.

Contents of a standard DSI carried out by BNC

1. Introduction

2. Ship Particulars

3. Precalculated damage scenarios

3.1 Penetrations of side shell plating

3.2 Strikes by a large vessel

3.3 Groundings

3.4 Bow crushings

3.5 Summary table

4. On board computer program for damage stability calculations

5. Conclusions

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